BER performance of multi user scheduling for MIMO-STBC and MIMO-OFDM broadcast network with imperfect CSI

One of the most efficient techniques that is inevitable for the state of the art communication system in today's wireless communication is multiple-input multiple-output (MIMO) technology. MIMO provides robustness against multipath fading using spatial diversity gain, and increases data rate by spatial multiplexing gain. These gains are achieved due to the usage of several antennas. This paper presents multiuser (MU) MIMO downlink system under imperfect channel state information (CSI) and heterogeneous user signal-to-noise ratio (SNR) profile. MU MIMO essentially provides multiuser diversity gain. System capacity is increased by choosing the users experiencing better channel parameters. We have used normalized SNR based scheduler to select a user for data transmission. The outcomes of these techniques are higher data rate and transmitting long range without need of much power or bandwidth. Alamouti's space time block code (STBC) has been used in this work to increase the transmit diversity, which improves reliability of data transfer. In this paper a comparative performance evaluation of MU MIMO-STBC and MIMO-OFDM has been presented. Moreover the effects of various factors such as imperfection of CSI, heterogeneity of network are investigated for these schemes.